1. Prevent leakage while adjusting the pressure balance for the water tank to keep the water level balance.
2. With the increasement in water temperature, the cooling water begins to expand. once the pressure exceeds the release pressure (1.3bar), the water tank cap string will open and let the cooling water flow to the subsidiary water tank for storage.
3. On the contrary, with the decreasement in water temperature, the cooling water begins to shrink which causes vacuum inside the water tank. then, the water tank cap string will open and let the cooling water flow from the subsidiary water tank to the water tank, so as to keep the water level balance.
4. Safety water tank cap with temperature gauge can show you the accurate water tank temperature without launching the engine.and the silicone inner stopper helps enhance the heatproof function and the compactness of the tank cap!
5. Free you of the worries of engine damage by high water temperature. universal for all water tanks.